Recently, in the field of endoscopes, a capsule endoscope, which is a swallowable endoscope, provided with an imaging function and a radio communication function emerges, and a radio in-vivo information acquiring system, which is a capsule endoscope system, that acquires in-vivo image data imaged by the capsule endoscope is under development. In this radio in-vivo information acquiring system, the capsule endoscope is swallowed from a mouth of a subject for observation (examination) and it is naturally discharged from the subject. During this time, the capsule endoscope moves in the interior of the subject such as the interior of internal organs including a stomach and a small intestine according to the peristaltic activity, and images the interior of the subject in a predetermined interval such as in an interval of 0.5 seconds.
While the capsule endoscope moves in the interior of the subject, the image data imaged by the capsule endoscope is transmitted to the exterior by a radio communication, and is received by a receiving apparatus via a receiving antenna provided outside. The receiving apparatus reconstructs the image data based on the radio signal (also called as radio frequency signal) sequentially received via the receiving antenna. Through this process, the in-vivo image data imaged by the capsule endoscope is acquired. The receiving apparatus sequentially stores the acquired image data into its memory. The subject carries the receiving apparatus having the radio communication function and the memory function so as to freely move while the subject swallows the capsule endoscope and it is naturally discharged. Thereafter, a doctor or a nurse takes out the image data stored in the memory of the receiving apparatus and inputs it to a display device. The display device then displays on its display the in-vivo image such as an image of internal organs based on the obtained image data. The doctor or the nurse uses the image of internal organs or the like displayed on the display to diagnose the subject (For example, see Patent Document 1).
Generally, such a receiving apparatus is configured to dispersedly arrange on the exterior of the subject (on the surface of the subject's body, for example) a plurality of antennas that receive the radio frequency signal transmitted from the capsule endoscope and to select and switch one antenna that makes few receiving errors of the radio frequency signal so as to receive the radio signal. There has been proposed a technique in which a connector that connects a module having an antenna module assembled therein for imparting versatility to the receiving apparatus is changed so as to correspond to a plurality of interfaces (Patent Document 2).
There has been proposed another technique for keeping apart a radio controlling device and a receiving apparatus. In this technique, the receiving apparatus and the radio controlling device that controls a radio are separately built to prevent noise from entering the receiving apparatus, and the both devices are connected by a connecting cable (Patent Document 3).
Patent Document 1: Japanese Patent Application Laid-open No. 2001-231186
Patent Document 2: Japanese Patent Application Laid-open No. 2004-118308
Patent Document 3: Japanese Patent Application Laid-open No. H5-218984